Abstract: A method for processing data packets in a communication network includes establishing a path for a flow of the data packets through the communication network. At a node along the path having a plurality of aggregated ports, a port is selected from among the plurality to serve as part of the path. A label is chosen responsively to the selected port. The label is attached to the data packets in the flow at a point on the path upstream from the node. Upon receiving the data packets at the node, the data packets are switched through the selected port responsively to the label.

Abstract: A method for communication includes operating a network element, which includes multiple ports and multiple interconnected processing units, such that each processing unit is assigned to process packets that are communicated over a respective set of one or more of the ports. Each processing unit stores a respective list, which indicates one or more multicast packet streams that are permitted for forwarding by the network element, and further indicates a respective subset of the ports over which each of the multicast packet streams is permitted for forwarding. A request relating is disturbed among the multiple processing units, and the respective list in each processing unit is updated responsively to the request. Multicast packets associated with the given multicast packet stream are forwarded selectively by the processing units in accordance with the respective updated lists.

Abstract: A method for communication includes configuring a plurality of ring nodes to communicate over a communication network that includes two or more overlapping communication rings, each ring including two unidirectional ringlets in mutually-opposite directions. A data packet including one or more header fields is accepted at an ingress ring node. An egress ring node to which the data packet is to be forwarded by the ingress ring node is determined. A subset of the rings including one or more common rings that are connected to both the ingress and egress ring nodes is identified. A ringlet of a ring among the one or more common rings is selected responsively to a respective value of at least one of the header fields of the packet. The data packet is forwarded from the ingress ring node to the egress ring node over the selected ringlet.

Abstract: A method for communication over a bi-directional ring network includes provisioning a virtual private local area network service (VPLS) over the bi-directional ring network. The VPLS includes connection termination points provisioned respectively on a plurality of the nodes so as to connect each of the plurality of the nodes to a second network external to the ring network. As long as the nodes and spans are fully operational, one or more of the connection termination points are maintained in a deactivated state, so that no more than one of the connection termination points to the second network is active. The nodes exchange messages indicative of a failure associated with the bi-directional ring network, causing at least one of the deactivated connection termination points to be activated so as to maintain connectivity among the users of the VPLS without creating a loop in the VPLS via the second network.

Abstract: A method for communication via a ring network that includes a plurality of nodes. The method includes receiving at a first node in the ring network a data packet transmitted over a virtual private LAN service (VPLS), the data packet including an identification of the VPLS. The first node reads the identification from the data packet. Responsively to reading the identification, the first node forwards the data packet to at least one second node in the ring network that is associated with the VPLS.

Abstract: A method for processing data packets in a communication network includes establishing a path for a flow of the data packets through the communication network. At a node along the path having a plurality of aggregated ports, a port is selected from among the plurality to serve as part of the path. A label is chosen responsively to the selected port. The label is attached to the data packets in the flow at a point on the path upstream from the node. Upon receiving the data packets at the node, the data packets are switched through the selected port responsively to the label.

Abstract: A method for data communications includes receiving a time-division-multiplexed (TDM) input signal carrying a payload comprising data and determining whether the data comprise synchronous or non-synchronous data. A first encapsulation scheme is selected if the data comprise synchronous data, and a second encapsulation scheme is selected if the data comprise non-synchronous data. The data are encapsulated for transmission over a packet-switched network in accordance with the selected encapsulation scheme.

Abstract: A functionality and method for determining aggregate data transit bandwidth requirements for the nodes of an Ethernet ring network for traffic management and to improve the operation, efficiency, and Quality of Service. An aggregate bandwidth database is produced, based on a priori knowledge of the ring network, including topology, path utilization, bandwidth sharing, and failure protection scenarios. Aggregate bandwidth requirements are determined independent of the actual real-time data traffic rates, and without requiring any actual real-time data traffic rate information. Aggregate bandwidth is automatically determined upon configuration or reconfiguration of the ring network.

Abstract: A method for communication includes configuring a plurality of ring nodes to communicate over a communication network that includes two or more overlapping communication rings, each ring including two unidirectional ringlets in mutually-opposite directions. A data packet including one or more header fields is accepted at an ingress ring node. An egress ring node to which the data packet is to be forwarded by the ingress ring node is determined. A subset of the rings including one or more common rings that are connected to both the ingress and egress ring nodes is identified. A ringlet of a ring among the one or more common rings is selected responsively to a respective value of at least one of the header fields of the packet. The data packet is forwarded from the ingress ring node to the egress ring node over the selected ringlet.

Abstract: A method for communication includes, in a communication network that includes multiple ring nodes arranged in at least first and second ring networks that are connected by two or more of the ring nodes serving as interconnect nodes, accepting at the two or more interconnect nodes respective copies of a data packet, which is sent from a source user node connected to the first ring network. An attribute is extracted from the respective copies of the data packet at each of the interconnect nodes, and a predefined mapping function is applied to the extracted attribute so as to select a single interconnect node for forwarding the data packet to the second ring network. A single copy of the data packet is forwarded to the second ring network only from the selected interconnect node, while refraining from forwarding other copies from the other interconnect nodes.

Abstract: A method for communication includes configuring a plurality of ring nodes to communicate over a communication network that includes two or more overlapping communication rings, each ring including two unidirectional ringlets in mutually-opposite directions. A data packet including one or more header fields is accepted at an ingress ring node. An egress ring node to which the data packet is to be forwarded by the ingress ring node is determined. A subset of the rings including one or more common rings that are connected to both the ingress and egress ring nodes is identified. A ringlet of a ring among the one or more common rings is selected responsively to a respective value of at least one of the header fields of the packet. The data packet is forwarded from the ingress ring node to the egress ring node over the selected ringlet.

Abstract: A method for communication includes operating a network element, which includes multiple ports and multiple interconnected processing units, such that each processing unit is assigned to process packets that are communicated over a respective set of one or more of the ports. Each processing unit stores a respective list, which indicates one or more multicast packet streams that are permitted for forwarding by the network element, and further indicates a respective subset of the ports over which each of the multicast packet streams is permitted for forwarding. A request relating to reception of a given multicast packet stream is received from a client. The request is distributed among the multiple processing units, and the respective list in each processing unit is updated responsively to the request. Multicast packets associated with the given multicast packet stream are forwarded selectively by the processing units in accordance with the respective updated lists.

Abstract: A method for budgeted learning of link information in a network includes providing a database to contain the link information, for use by an entity connected to the network in transferring traffic over the network, and setting a maximum rate for addition of entries to the database. New entries to be added to the database are determined responsive to the traffic on the network during a learning period. The new entries are added to the database only if the addition of the entries during the learning period has not exceeded the maximum rate.

Abstract: A maintenance entity for an Ethernet Connectivity Fault Management (CFM) domain. The maintenance entity comprises a port definer module and a connection which is connected to a group of aggregated link. The port definer module examines a designated link of the group by forwarding CFM messages via the designated link.

Abstract: A functionality and method for determining aggregate data transit bandwidth requirements for the nodes of an Ethernet ring network for traffic management and to improve the operation, efficiency, and Quality of Service. An aggregate bandwidth database is produced, based on a priori knowledge of the ring network, including topology, path utilization, bandwidth sharing, and failure protection scenarios. Aggregate bandwidth requirements are determined independent of the actual real-time data traffic rates, and without requiring any actual real-time data traffic rate information. Aggregate bandwidth is automatically determined upon configuration or reconfiguration of the ring network.

Abstract: A method for communication includes receiving an Internet Protocol Multicast (IPMC) packet for delivery to multiple subscribing hosts. The IPMC packet is encapsulated in a plurality of unicast frames that are respectively addressed to the subscribing hosts for transmission via a Layer 2 network to the subscribing hosts.

Abstract: A method for testing a network element that includes multiple ports includes assigning one or more of the ports to serve as input and output test ports. One or more of the ports other than the test ports are terminated with respective loopback connections. The network element is configured to forward packets entering the network element at the input test port, so as to cause the packets to be distributed among the terminated ports and to exit the network element, after re-entering the network element at one or more of the terminated ports, at the output test port. A first sequence of the packets is applied to the input test port, and a second sequence of the packets exiting the network element at the output test port is received. An operation of the network element is verified by evaluating the second sequence.

Abstract: A method for communication includes encapsulating multiple data packets, which carry data and have respective drop precedence (DP) values selected from a range of possible DP values, to produce a concatenated frame of a transport protocol. A composite drop precedence (CDP) value is assigned from the range to the concatenated frame using a pseudo-random assignment function that depends on a distribution of the DP values of the data packets in the concatenated frame. The concatenated frame is transported through a communication network using the transport protocol, in accordance with the pseudo-randomly assigned CDP value.

Abstract: A network node in a communication network includes a plurality of ports, at least a subset of which is grouped in a link aggregation (LAG) group. The node includes packet processing logic, which is coupled to receive data packets having respective destination addresses that specify forwarding the packets to groups of multiple recipients through at least one of the ports and to process the data packets so as to forward only a single copy of each of the data packets via the output ports in the subset, while distributing forwarded copies of the data packets among the output ports in the subset so as to balance a traffic load within the LAG group.

Abstract: A method for communication is used in a communication network that includes multiple ring nodes arranged in at least first and second ring networks, which are connected by one or more of the ring nodes serving as interconnect nodes. A data packet is accepted from a source user node served by the first ring network, for forwarding to a destination user node served by the second ring network. An identifier, which identifies an interconnect node in the first ring network through which the data packet is to be forwarded to the second ring network, is attached to the data packet in the first ring network. The data packet is forwarded over the first ring network, accepted at the interconnect node and, responsively to the identifier, forwarded from the interconnect node to the second ring network. The data packet is forwarded over the second ring network to the destination user node.